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					ENVIRONMENTAL PRIORITY SERVICE INC.     7193 E. Benfield Rd., Salina, Kansas 67401
                                       Office: (785) 823-6205 Fax: (785) 823-6412




         ENVIRONMENTAL PRIORITY SERVICE, INC.




               GROUNDWATER, SOIL & SOIL GAS

             COLLECTION AND ON-SITE ANALYSIS

          UTILIZING HEATED HEADSPACE METHOD




                  FIELD PROCEDURES MANUAL

                             August, 2006
                           Revised May 2007




GENERICHEADSPACESOPS                                                       Page 1
Field Procedures Manual
January, 2006                                                                                   Environmental Priority Service, Inc.



                                              TABLE OF CONTENTS
                                                                                                                                        Page No.

SAMPLING EQUIPMENT

       EQUIPMENT .....................................................................................................................3
                 Probing Machine and related sampling equipment ............................................................. 3
                 Analytical Equipment ......................................................................................................... 3

       EQUIPMENT SPECIFICATIONS .............................................................................. 3-4
                 Gas Chromatographs........................................................................................................ 3-4
                 Data Integrators................................................................................................................ 3-4
                 Megabore Column .............................................................................................................. 4

       PRELIMINARY INSTRUMENT OPERATING CONDITIONS ................................4


SAMPLE COLLECTION & ANALYSIS

       ANALYTES OF INTEREST ............................................................................................5

       SAMPLE COLLECTION PROCEDURES ....................................................................5
                 Soil Gas Sampling Procedures ............................................................................................ 5
                 Soil Sampling Procedures ................................................................................................ 5-6
                 Groundwater Sampling Procedures .................................................................................... 6

       VERIFICATION OF REPORTING LIMITS ............................................................ 6-7
                 Verification of Soil Gas Reporting Limit ........................................................................ 6-7
                 Verification of Groundwater/Soil Reporting Limit ............................................................ 7

       CALIBRATION OF GAS CHROMATOGRAPH ................................................... 8-10
                 Calibration of Gas Chromatograph for Soil Gas Samples ............................................... 8-9
                 Calibration of Gas Chromatograph for Groundwater/Soil Samples .............................. 9-10

       FIELD SCREENING & ANALYSIS ....................................................................... 10-12
                 Soil Gas Analysis .............................................................................................................. 10
                 Soil Analysis ..................................................................................................................... 11
                 Groundwater Analysis ................................................................................................. 11-12

       QUALITY CONTROL/QUALITY ASSURANCE ................................................ 12-13
                 Calibration Check ............................................................................................................. 12
                 Blank Samples .................................................................................................................. 12
                 Duplicate Samples ............................................................................................................ 13




GENERICHEADSPACESOPS                                                                                                                        Page 2
Field Procedures Manual
January, 2006


                                      SAMPLING EQUIPMENT


EQUIPMENT

Probing Machine and Related Sampling Equipment
   Geoprobe 4200 & 5400 Series Hydraulic Probe Machines
   Geoprobe 6620 Track Unit
   On-board vacuum/volume system for vapor extraction
   Hardened alloy steel probe roads (1.25” x 3,4,5’ flights)
   Larger diameter (2.125” & 3.25”) probe rods for mini-well installation and track unit use
   Hollow Stem Augers for shallow (<30’) 2” conventional wells
   Soil sampling tools: 4 & 5 ft. macros & 4 & 2 ft. discreet large-bore sampler
   Groundwater sampling tools: 2 & 4’ mill-slotted, 4’ stainless steel screen
   Groundwater screen implants
   Expendable Drive Points
   Polyethylene tubing for sampling
   Soil Gas sampling tools: PRT system
   Soil Electrical Conductivity System
   Grout Pump
   Generators
   Water Tanks
   Power Washers
   Holding tanks

Analytical Equipment
   Shimadzu model GC-14A laboratory grade gas chromatograph
   Hewlett Packard model 5890A Series 2 computerized laboratory gas chromatograph
   Shimadzu model CR-7A Chromatopac Data Processor for Chromatography
   P/E Nelson model 970A chromatography signal interface
   P/E Nelson Analytical Turbochrom 4.0 series integration software
   Three detectors – Flame Ionization (FID), Electron Capture (ECD), & Photoionization (PID)
   Temperature-controlled laboratory oven
   Odyssey Spectrophotometer

EQUIPMENT SPECIFICATIONS

Gas Chromatograph (GC-14A)
   Two temperature-controlled injector ports and three detectors (FID, ECD, & PID)
   Temperature Range from -80C to +399C
   Provides 5 Program Ramping Stages with a maximum temperature range of 40C/minute
   Injection Port Range is 399C




GENERICHEADSPACESOPS                                                                            Page 3
Field Procedures Manual
January, 2006                                                        Environmental Priority Service, Inc.




Data Integrator (CR-7A)
   Contains 2 imprint channels.
   Maximum peak number for identification: 1000 peaks
   Minimum peak width processed: 0.04 seconds (width at half-height)
   Linearity: less than 0.1%
   Dynamic Range: 10E6
   Disk Drives: 3.5” hard disk drive (40 Mbyte), 3.5” floppy disk drive (1.6 Mbyte)

Gas Chromatograph (HP-5890 Series 2)
   Two temperature-controlled injector ports and three detectors (FID, ECD, & PID)
   Temperature Range from -80C to +450C
   Connected in-line with Tekmar Purge and Trap
   Provides 3 Program Ramping Stages with a maximum temperature range of 40C/minute
   Injection Port Range is 0-399C


Signal Interface/Chromatography Integrator (Nelson model 970A)
   Contains 2 imprint channels.
   Maximum peak number for identification: 1000 peaks
   Minimum peak width processed: 0.04 seconds (width at half-height)
   Linearity: less than 0.1%

Megabore Column
   Maximum temperature: 260C
   Type of Column: J&W DB-624
   Length of Column: 30 meters
   Outer Diameter: 0.543 mm


PRELIMINARY INSTRUMENT OPERATING CONDITIONS

The Hewlett Packard 5890A Series 2 Gas Chromatograph or the Shimadzu Gas Chromatograph 14-A
(GC), each equipped with a photo-ionization detector (PID) and an electron capture detector (ECD) in
series, will be utilized to analyze the samples. The GC column temperature will run isothermally for 3
minutes at 50 C, then temperature ramp at 10C/min to 170C, while the injector temperature is at 180
C and the detectors are at 225 C.

It should be noted that the instrument operating conditions noted above are preliminary. The conditions
will be modified in the field, as necessary, to optimize instrument performance.

                                                *****




GENERICHEADSPACESOPS                                                                              Page 4
Field Procedures Manual
January, 2006                                                           Environmental Priority Service, Inc.



                          SAMPLE COLLECTION & ANALYSIS


ANALYTES OF INTEREST
Soil gas, soil and groundwater samples will be collected from the sites of interest. The target compounds
analyzed for during this project are cis-1,2-dichloroethene (cis-1,2-DCE), trichloroethene (TCE),
tetrachloroethene (PCE), and carbon tetrachloride (CCL4). For optimum detection of the analytes of
interest, the gas chromatograph (GC) will be equipped with a photoionization detector (PID) and an
electron capture detector (ECD) in series. The ECD is extremely sensitive to TCE and PCE and will be
used as a confirmation back-up tool, while the PID will be calibrated to and used for actual analysis of
cis-1,2-DCE, TCE, and PCE. The ECD will be used to quantify CCL4.


SAMPLE COLLECTION PROCEDURES
To minimize cross-contamination of samples, each test hole is probed with pre-cleaned sampling rods.
Pre-cleaning consists of steam-cleaning, washing with Alconox soap, and rinsing with deionized water.
Enough probe rods are available so that they are used only once between decon periods. In addition,
disposable gloves, polyethylene tubing, and syringes are used for sample collection and analysis to
minimize cross-contamination. All disposable equipment is used only once.

Procedures specific to the collection of soil gas, soil and groundwater are detailed in the following
paragraphs.


Soil Gas Sampling Procedure
Soil gas sampling procedures include advancing 1.25-inch outer diameter (O.D.) probe rods with a
threaded point holder and disposable point to the desired sampling depth on each test hole. Polyethylene
tubing (1/4” dia.) is then lowered down the inner diameter of the probe rods and threaded onto the
threaded point holder. An o-ring is utilized to ensure a tight seal surrounding this threaded fitting. The
probe unit is then used to retract the rods approximately 2- to 4-inches, thereby disengaging the
disposable drive point attached to the threaded point holder. Once a space or void has been made for soil
gas extraction, the tubing is purged, utilizing the on-board vacuum system, to remove any extraneous air
present in the polyethylene tubing.

Once purged, a soil gas sample is collected using a disposable syringe. The soil gas sample is collected
by first pinching off the upper sample tubing, puncturing the tubing directly above the upper probe rod
with the syringe, and evacuating 0.20 cc of soil gas from within the tubing into the syringe. The sample,
0.20 cc of soil gas, is then immediately injected into the GC for analysis.

Soil Sampling Procedure
Soil sampling procedures include vertically profiling the soils to the desired sampling depths or probe
refusal. Continuous profiling procedures include attaching a 4-ft. in length Geoprobe macro-core soil
sampler to the leading probe rod, and advancing the sampler in 4-ft. increments from the ground surface
to the desired sampling depths. Discreet profiling procedures include attaching a closed piston-assembled
4-ft. in length Geoprobe macro-core soil sampler to the leading probe rod, and advancing the sampler in
4-ft. increments from the ground surface to the desired sampling depth. Once at depth, small diameter


GENERICHEADSPACESOPS                                                                                    Page 5
Field Procedures Manual
January, 2006                                                           Environmental Priority Service, Inc.


(1/8”) extension rods are lowered down the I.D. of the probe rods until they make contact with the piston
rod and the reverse-threaded, piston rod stop pin. The stop pin is unthreaded freeing up the inner piston
rod and driving point. The 4-ft. sampler is then advanced filling the sample tube with the discreet sample.
The sampler is equipped with an inner PVC, transparent liner, useful for logging purposes. The filled
liners are placed on visqueen and placed on the ground surface for visual observation. Soil samples are
then collected and logged by Client personnel. Once a selected sample has been determined, EPS will
conduct the on-site analysis of the soil samples. Selected duplicate samples will be sent from the Client
to a certified laboratory for analysis.


Groundwater Sampling Procedure
Once it has been determined that depth to groundwater is within sampling range of the hydraulic probe
and that sufficient water is available for sampling, groundwater samples will be collected for analysis. A
1-inch by 2-foot length of mill-slotted groundwater sampling tool, which is attached to the leading probe
rod, is advanced in 3-foot sections to the desired sampling depth at each test hole. A larger diameter (1.5-
inch) pre-probe point is connected to the bottom end of the mill-slotted tool. This pre-probe point is used
to prevent the mill-slots from plugging with sediment as the rods are advanced to depth. If conditions do
not warrant mill-slot usage due to the presence of too much clay or too small fines, then a Geoprobe
SP-15 Screen Point Sampler will be used. This sampler is equipped with an inner 4-foot length of mesh-
wire screen. Once the rods and SP-15 sampler are advanced to depth, the rods are retracted
approximately 4 feet, which exposes the inner screen. Once groundwater has infiltrated the sampler, a
groundwater sample can be collected.

Prior to sample collection, a groundwater depth measurement will be taken using a Solinst water level
indicator. Static water levels are taken by lowering the water level indicator inside the probe rods until
contact with water occurs. The water level is then measured to within 1/100th of an inch.

To collect the groundwater sample, the on board vacuum/volume system, a peristaltic pump, or a ball-
and-seat check valve system is used. Whichever system is utilized, depending on hydrologic conditions,
3/8” polyethylene tubing will be used to collect the groundwater samples. The 3/8” tubing is lowered
down the inside of the probe rod until it reaches the bottom of the mill-slotted section or SP-15 sampler.
An up-down motion of the tubing allows groundwater to infiltrate up through the tubing to the ground
surface if the ball-and-seat check valve system is used. Utilizing the vacuum/volume system,
groundwater is extracted through the tubing by using a vacuum of no more than 21 inches of mercury.
Once a sufficient amount of the groundwater has been purged from the sampling string, the tubing is
pinched off at the ground surface and pulled from the probe rods. Groundwater is then immediately
transferred from the lower end of the tubing directly into 40-ml vials. The vials are filled to minimize the
headspace, and the samples are placed on ice and set aside awaiting analysis. Depending upon
groundwater availability, a minimum of two 40-mL vials is typically collected at each sample location.


VERIFICATION OF REPORTING LIMITS
The reporting limit for each compound is determined by the sensitivity of each detector that is utilized.
For example, based upon instrument performance using heated headspace the PID is typically sensitive to
cis-1,2 DCE, TCE and PCE at or below 2 parts per billion (ppb). Similarly, the ECD is sensitive to CCL4
at or below 2 parts per billion. Therefore, the reporting limits for cis-1,2 DCE, TCE and PCE would be
anticipated to be at 2 ppb in non-diluted samples. When running a different detector, or dual detectors,
the same idea would apply to the ECD or FID pertaining to compounds to be screened. Prior to field
activities, the reporting limits will be verified as described in the following paragraphs.


GENERICHEADSPACESOPS                                                                                  Page 6
Field Procedures Manual
January, 2006                                                            Environmental Priority Service, Inc.


Verification of Soil Gas Reporting Limits
To verify the detection limit, a standard is made for each analyte of interest, or a commercially prepared
standard is utilized. The gas standard is made from stock solutions of the target compounds preserved in
methanol. The distributor (Chem Service) guarantees the concentrations of the stock solutions
(including DCE, TCE, PCE and CCL4) are 100ug/ml plus or minus 5% in methanol. To produce a 2 ppb
gas standard, 20 microliters (l) of each stock solution is injected into a 1000-ml glass bulb. To produce
a 5 ppb gas standard, 50 l of the stock solution is injected into a 1000-ml glass bulb, and so on.

The verification of the detection limit is made by analyzing three (3) injections of the standard prepared at
or below the chosen reporting limit (i.e., 2 ppb). If the instruments signal to noise ratio is 10.1 or greater,
then the detection limit has been verified. If this criterion is not met, then the detection limit should be
increased accordingly.

In order to meet data input requirements for the Shimadzu and P/E Nelson Analytical Data Processors, the
average retention time and peak area is calculated for each analyte of interest during the verification
process. The result of an internal 3-point calibration curve automatically determines a response factor,
which enters into the Identification Table of the Data Processor. The response factor, as defined/required
by the Data Processor, is determined by dividing the known concentration of each individual compound
within the standard by its average peak area. Appropriate retention time windows are selected for the
identification of each compound, based on degree of separation.


Verification of Groundwater/Soil Reporting Limits
To verify a 2 g/L reporting limit, a standard is made for each analyte of interest. The liquid standard is
made from stock solutions of the target compounds preserved in methanol. The stock solutions contain
concentrations of the stock solutions (including DCE, TCE, PCE, and CCL4) at 100ug/ml plus or minus
5% in methanol.

A 1:5 Working Standard is prepared using the stock solutions. Standards are prepared in a 50cc
volumetric flask for each calibration level using this compound mixture. Three 40-ml vials are then
prepared by transferring 20-ml of the Working Standard from the volumetric glassware. Standards may
also be prepared by spiking a half full 40-ml vial with the compound mixture. The vials are placed in a
temperature-controlled oven at approximately 90C for approximately 15 minutes. Once a vial has been
thoroughly heated, 0.20 cc of headspace from within the vial is collected with a syringe and immediately
injected into the GC for analysis.

The verification of the reporting limit is made by analyzing three (3) injections of a standard prepared at
or below the chosen reporting limit (i.e., 2 g/L). If the instruments signal to noise ratio is 10.1 or
greater, then the reporting limit has been verified. If this criterion is not met, then the reporting limit
should be increased accordingly.

In order to meet data input requirements for the Shimadzu and P/E Nelson Analytical Data Processors, the
average retention time and peak area is calculated for each analyte of interest during the verification
process. The result of an internal 3-point calibration curve automatically determines a response factor,
which enters into the Identification Table of the Data Processor. The response factor, as defined/required
by the Data Processor, is determined by dividing the known concentration of each individual compound
within the standard by its average peak area. Appropriate retention time windows are selected for the
identification of each compound, based on degree of separation.



GENERICHEADSPACESOPS                                                                                    Page 7
Field Procedures Manual
January, 2006                                                                   Environmental Priority Service, Inc.


CALIBRATION OF GAS CHROMATOGRAPH
Prior to the start of field activities, the GC will be calibrated using a 3-point calibration. Concentrations
of 2, 10, and 20 ppb are typically used for the initial calibration for fuel compounds and chlorinated
solvents. Broader calibration ranges may need to be utilized if high concentrations of the analytes of
interest are detected within the field. This may be accomplished by a calibration check of a concentration
range equivalent to the high concentration sample. It is anticipated that the initial calibration may be
sufficient for the entirety of this field activity. Calibrations will be re-established if necessary. The
stability of the calibration will be assessed during the field program through the use of calibration checks
(see Page 12,13 Quality Control / Quality Assurance).

A chromatograph and area report that was generated by the chromatography software will be provided for
each standard that is analyzed. Calibration reports that are generated by the chromatography software
will also be provided.


Calibration of Gas Chromatograph for Soil Gas Samples
Standards are commonly made at concentrations of 2, 10, and 20 ppb for each chlorinated analyte of
interest. However, in situations in which higher concentrations of target analytes are anticipated, a
broader range of standard concentrations will be utilized. The gas standard is made from stock solutions
of the target compounds preserved in methanol. Concentrations of the stock solutions (including DCE,
TCE, PCE and CCL4) are 100ug/ml plus or minus 5% in methanol. To produce each concentration of the
gas standard, the appropriate volume of each stock solution is injected into a 1000-ml glass bulb.

Once the gas standard has been made, a known volume (typically 0.20 cc) of the gas standard is injected
into the GC for each concentration. A calibration factor is calculated for each concentration of each
target compound. The ratio of the detector response (peak area or peak height) to the concentration of
analyte in the calibration standard is defined as the calibration factor. The CF is calculated as follows:


                 CF =       Peak Area (or Peak Height) of the Compound in the Standard
                             Concentration of the Compound Injected (ppb or g/L)

To evaluate the linearity of the initial calibration, the P/E Nelson integration software calculates a
correlation coefficient (CC) by linear regression, from three calibration injections using a straight-line fit.
The mean CF, the standard deviation (SD), and the relative standard deviation (RSD) can be manually
calculated as follows:

                                              n

                                              CF
                                             i 1
                                                         i
                                                                 CF1 ppb  CF5 ppb  CF10 ppb
                           meanCF  CF                      
                                                    n                           3


                    CF  CF 
                     n

                                            CF                                                  
                                    2
                                                                 2                  2                 2
                             i
                                                         CF  CF5 ppb  CF  CF10 ppb  CF
          SD       i 1
                                        
                                               1 ppb

                            n 1                                            2




GENERICHEADSPACESOPS                                                                                         Page 8
Field Procedures Manual
January, 2006                                                              Environmental Priority Service, Inc.




                                                 SD
                                        RSD         100
                                                 CF

Note: In the preceding calculations n is the number of calibration standards and RSD is expressed as a
percentage (%).

If the RSD of the calibration factors is less than or equal to 25% over the calibration range for each
compound of interest, then linearity through the origin is assumed. The average calibration factor (mean
CF) can then be used to determine sample concentrations by manual calculation.

If the RSD for any target analyte exceeds 25%, then one or more of the following corrective actions will
be necessary and will be performed in the following order:

   Check the instrument operating conditions
   Review the results (peak area) and subsequent calculations that do not meet the linearity criteria. If
    the problem appears to be associated with a single standard or injection, that standard/injection may
    be reanalyzed and the calibration statistics recalculated.
   Re-calibrate until all compounds meet the linearity criteria.


Calibration of Gas Chromatograph for Groundwater/Soil Samples
Standards are commonly made at concentrations of 2, 10, and 20 g/L for each analyte of interest. Please
note that calibration ranges may be increased within the field if high concentrated samples detected
cannot be diluted within the 20 ppb calibration range. A photoionization detector (PID) will assist in
determining sample locations with elevated concentrations of target analytes. This may be accomplished
by a calibration check of a concentration range similar to the high concentration sample detected within
the field. The liquid standards are made from stock solutions of the target compounds preserved in
methanol. The stock solutions contain concentrations at 100ug/ml plus or minus 5% in methanol. A 1:5
Working Standard stock mixture is prepared using these stocks.

Working Standards for each calibration concentration (i.e. 2, 10, and 20 g/L) are prepared from
Intermediate Standards. Following preparation in a 50 cc volumetric flask, 20-ml of each calibration
concentration is transferred to a 40-ml vial. The standard can also be prepared by spiking a half full 40-
ml vial with the compound mixture. The vials are placed in a temperature-controlled oven at
approximately 90C for approximately 15 minutes. Once a vial has been thoroughly heated, 0.20 cc of
headspace from within the vial is collected with a syringe and immediately injected into the GC for
analysis.

Linear regression is then used by the Nelson software to evaluate the linearity of the initial 3-point
calibration by internal calculation of a correlation coefficient (r) that represents the “fit” of a straight line
to the data. A value of r=1.00 indicates a perfect fit. Calibration is determined acceptable when r 0.98.
Alternatively, the coefficient of determination (r2) can be determined. Calibration is determined
acceptable when r2 0.97. Calibration of certain compounds with low detector response or short shelf life
may be considered acceptable at a slightly lower coefficient. The Client will approve any deviance from
the r 0.98 (or r2 0.97) criteria prior to analysis of any samples.




GENERICHEADSPACESOPS                                                                                      Page 9
Field Procedures Manual
January, 2006                                                            Environmental Priority Service, Inc.


While the linear regression is performed internally by the Nelson software, it can also be performed
manually using statistical procedures. The linear regression calculations produce the slope and y-
intercept of a line of peak area versus compound concentration. The linear equation is as follows:

                y=      ax + b

Where:
         y=     Peak area or height
         a=     Slope of the line
         x=     Concentration of target compound
         b=     y-intercept

Alternatively, linearity of calibration can be manually evaluated using the average CF (CF). Equations
for the manual calculation of the mean CF, the standard deviation (SD), and the relative standard
deviation (RSD) are used.

Once each standard has been analyzed, a calibration factor is calculated (Shimadzu software) for each
concentration of each target compound. The equations for the mean CF, the standard deviation (SD), and
the relative standard deviation (RSD) can be done manually as previously presented (See Page 8,
Calibration of Gas Chromatograph for Soil Gas Samples).


FIELD SCREENING & ANALYSIS

Soil Gas Analysis
At the beginning of each day of analysis, a gaseous calibration check and method blank analysis will be
performed. (See Page 12, 13) Quality Control/Quality Assurance, for further discussion of calibration
checks and method blanks.) Once it has been established that both the calibration check and method
blank meets the acceptance criteria, field samples are analyzed. As previously presented, a soil gas
sample is collected from the sampling tubing using a disposable syringe. The sample, 0.20 cc of soil gas,
is then immediately injected into the GC for analysis. After the analysis of 10 field samples, the method
blank analysis is repeated. The calibration check is repeated at the end of each day.

Once the calibration is established, or the response factor defined (Shimadzu software) and retention time
for each individual compound has been entered into the ID table of the GC, the GC’s Data Processor
identifies each compound and reports the concentrations directly. The concentration of an analyte in the
sample can also be calculated manually using the following equation:

                                  Concentration, ppb 
                                                             As D 
                                                             CF 
Where:
As     =        Peak area for the analyte in the sample

D        =      Dilution factor (dimensionless). If no dilution was necessary, D=1.

CF       =      Mean calibration factor from the initial gas calibration (area per ppb)




GENERICHEADSPACESOPS                                                                                 Page 10
Field Procedures Manual
January, 2006                                                           Environmental Priority Service, Inc.


If a sample exhibits a concentration that potentially saturates the detector, dilution will be necessary. For
soil gas samples, dilution refers to injection of a smaller volume of soil gas into the GC.

Soil Analysis
At the beginning of each day of analysis, an aqueous calibration check and method blank analysis will be
performed. (See Page 12, 13) Quality Control/Quality Assurance, for further discussion of calibration
checks and method blanks.) Once it has been established that both the calibration check and method
blank meets the acceptance criteria, field samples are analyzed. Following soil collection, 5 grams
of soil are transferred into a separate 40-ml vial. The vial is then filled to the half-full mark with
deionized water (approx. 20 mLs.). The vial is then shaken vigorously dissolving the soil into the DI
water. The vial is then placed into a temperature-controlled oven at 90C for approximately 15 minutes.
Once heated, the vial is removed from the oven, then 0.20 cc of headspace from within the vial is
collected with a disposable syringe, and the sample is immediately injected into the GC for analysis. After
the analysis of 10 field samples, the method blank analysis is repeated. The calibration check is repeated
at the end of each day.

Once the calibration and/or response factor (defined previously) and retention time for each individual
compound has been entered into the ID table of the GC, the GC’s Data Integrator identifies each
compound and reports the concentrations in g/L. The concentration of the compounds within the soil is
then converted to g/Kg by multiplying the concentration reported in g/L by the total volume of
headspace (21 mL, actual) within the vial divided by the weight of the soil collected and analyzed (5
grams).

If a sample exhibits a high concentration that will potentially saturate the detector, dilution may be
necessary. Using the “back-up” vial collected at the sampling location, dilution will be performed by
transferring less than 5 grams of soil into a 40-mL vial and adding deionized water until the total volume
reaches the half-full mark on the vial. The diluted sample is then analyzed as previously described. As
an alternative to preparing a dilution, a smaller volume of headspace could be injected into the GC. In
some cases, less soil may be used to increase dilution ranges.

Groundwater Analysis
At the beginning of each day of analysis, an aqueous calibration check and method blank analysis will be
performed. (See Page 12, 13) Quality Control/Quality Assurance, for further discussion of calibration
checks and method blanks.) Once it has been established that both the calibration check and method
blank meets the acceptance criteria, field samples are analyzed. Following groundwater collection, 20 ml
of groundwater is transferred into a separate 40-ml vial. The vial is then placed into a temperature-
controlled oven at 90C for approximately 15 minutes. Once heated, the vial is removed from the oven,
0.20 cc of headspace from within the vial is collected with a disposable syringe, and the sample is
immediately injected into the GC for analysis. After the analysis of 10 field samples, the method blank
analysis is repeated. The calibration check is repeated at the end of each day.

Once the calibration and/or response factor (defined previously) and retention time for each individual
compound has been entered into the ID table of the GC, the GC’s Data Integrator identifies each
compound and reports the concentrations directly. The concentration of an analyte in the sample can also
be calculated manually using the following equation:




GENERICHEADSPACESOPS                                                                                 Page 11
Field Procedures Manual
January, 2006                                                              Environmental Priority Service, Inc.




                                   Concentration, ug / L 
                                                               As D 
                                                                CF 
Where:
As     =        Peak area for the analyte in the sample

D       =       Dilution factor (dimensionless). If no dilution was necessary, D=1.

CF      =       Mean calibration factor from the initial aqueous calibration (area per g/L)


If a sample exhibits a concentration that may potentially saturate the detector, dilution will be necessary.
Using the “back-up” vial collected at the sampling location, dilution will be performed by transferring
less than 20 ml of groundwater into a 40-mL vial and adding deionized water until a total volume of 20
ml of liquid is in the vial. For example, a dilution factor of 2 would require 10 ml of groundwater sample
and 10 ml of deionized water. Likewise, a dilution factor of 5 would require 4 ml of groundwater sample
and 16 ml of deionized water. The diluted sample is then analyzed as previously described. As an
alternative to preparing a dilution, a smaller volume of headspace could be injected into the GC, or these
procedures may be used in combination.


QUALITY CONTROL / QUALITY ASSURANCE

Calibration Check
Calibration checks are performed to ensure that the relationship between instrument response and initial
calibration is valid over the duration of the field effort. Calibration check samples will be analyzed at the
beginning and end of each day of analysis. For the gaseous and aqueous calibration checks, a mid-point
standard will be utilized. Aqueous standards are prepared on-site. The calibration checks regarding both
aqueous and gas standards for each target analyte must fall within 25% of the true value. If this criterion
is not met, then a second calibration check standard will be analyzed. If the second standard also falls
outside of acceptance criteria, then the standards may be used to re-calibrate prior to further sample
analysis. If field screened samples exhibit analyte concentrations greatly exceeding initial calibration
ranges, calibration checks may include higher concentrations that reflect these levels.

Blank Samples

Method Blanks
Method blanks will be run at the beginning of each day and following every 10th sample to ensure a clean
system. For soil gas samples, the method blank consists of ambient air collected in a disposable syringe.
For groundwater samples, the method blank consists of reagent water placed in a 40-mL vial and heated
in the temperature-controlled oven for approximately 15 minutes at 90C. Once heated, 0.20cc of
headspace from the vial is injected into the GC. If a detection is noted within a method blank, then the
blank analysis will be repeated. If the associated field samples have similar detections, these samples will
be reanalyzed if sufficient back-up volume was able to be collected.




GENERICHEADSPACESOPS                                                                                   Page 12
Field Procedures Manual
January, 2006                                                         Environmental Priority Service, Inc.


Rinsate Blanks
Prior to the commencement of, or during sampling, rinsate blanks will be collected from syringes,
soil/groundwater sampling tools, stirring rods, and/or sample vials to ensure that no cross-contamination
has occurred. If compound detection is noted within a rinsate blank, then the equipment will be re-
cleaned. If the associated field samples have similar detections, these samples will be reanalyzed if
sufficient back-up volume was able to be collected.


Duplicate Samples
Duplicate samples are collected and analyzed to demonstrate the precision of the collection and analysis
process. Duplicate samples are collected and analyzed at a frequency of 10% of the total samples
collected. Since duplicate sample results are dependent on both collection and analysis, the optimal
deviation for duplicate samples is a relative percent difference (RPD) of less than or equal to 25%. The
RPD is calculated as follows:

                                                 C1  C2
                                       RPD 
                                                C1  C2   100
                                                    2

                Where:
                         C1 = Measured Concentration of the first sample
                         C2 = Measured Concentration of the duplicate sample
                         RPD = Relative Percent Difference

If the RPD between duplicate samples dramatically exceeds 25% and sufficient “back-up” sample volume
was able to be collected, the sample may be reanalyzed.

                                                 *****




GENERICHEADSPACESOPS                                                                              Page 13

				
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